The possibility of producing the biologically active material of the skin, ceramide, was studied using yeasts. The yeast strain that produced the most ceramide, Saccharomyces cerevisiae (KCCM 50515), was selected, and the optimal conditions for ceramide production were determined using shake-flask culture and batch fermentation. By measuring the production rate of ceramide at various pH values and temperatures, the optimal conditions for ceramide production were found to be pH 6.0 and 30 degrees C. When heat shock was applied to the cells for 1 h by increasing the culture temperature from 30 to 40 degrees C after cell growth, the amount of ceramide produced was increased 5.9-fold. A cell growth and ceramide production model was developed with Monod kinetics and the Leudecking-Piret model. It showed that ceramide production was increased when the cells were in the stationary phase.